<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
</head>
<body>
<script type="text/javascript">
	//alert(1);
	//var a = 15;
(function(w,d){
	this.a = 30;
	//d.body.style.background = 'black';
	//alert(w)
	//alert(licuan);
	//var a = 10;
//	alert(1);
})(window,document);
alert(window.a);	
</script>
</body>
</html>